Question

For each statement below, indicate which of Newton's Three Laws the statement represents.
A ball rolls directly across the floor until Luis gives it a kick.
Both a bowling ball and a tennis ball roll over your foot at identical speeds, but the force of the bowling ball causes much more pain.
Your riding lawn mower stalls, and as your friends push it, the force helps the lawn mower move until it gradually accelerates.
A firefighter turns on a water hose and is pushed backward by the force.
A soccer ball remains stationary until a player kicks it into motion.

Answer 1

1. A ball rolls directly across the floor until Luis gives it a kick. — Newton's First Law (inertia: an object in motion stays in motion unless acted on by a net external force).

2. Both a bowling ball and a tennis ball roll over your foot at identical speeds, but the force of the bowling ball causes much more pain. — Newton's Second Law (larger mass produces a larger force/impulse for the same change in motion; F = ma or F = dp/dt).

3. Your riding lawn mower stalls, and as your friends push it, the force helps the lawn mower move until it gradually accelerates. — Newton's Second Law (net force produces acceleration, F = ma).

4. A firefighter turns on a water hose and is pushed backward by the force. — Newton's Third Law (every action has an equal and opposite reaction: water pushed backward exerts an equal opposite push on the firefighter).

5. A soccer ball remains stationary until a player kicks it into motion. — Newton's First Law (an object at rest stays at rest until acted on by a net external force).